Glen P. Peters

Growth in emission transfers via international trade from 1990 to 2008

Despite the emergence of regional climate policies, growth in global CO2 emissions has remained strong. From 1990 to 2008 CO2 emissions in developed countries (defined as countries with emission-reduction commitments in the Kyoto Protocol, Annex B) have stabilized, but emissions in developing countries (non-Annex B) have doubled. Some studies suggest that the stabilization of emissions in developed countries was partially because of growing imports from developing countries. To quantify the growth in emission transfers via international trade, we developed a trade-linked global database for CO2 emissions covering 113 countries and 57 economic sectors from 1990 to 2008. We find that the emissions from the production of traded goods and services have increased from 4.3 Gt CO2 in 1990 (20% of global emissions) to 7.8 Gt CO2 in 2008 (26%). Most developed countries have increased their consumption-based emissions faster than their territorial emissions, and non–energy-intensive manufacturing had a key role in the emission transfers. The net emission transfers via international trade from developing to developed countries increased from 0.4 Gt CO2 in 1990 to 1.6 Gt CO2 in 2008, which exceeds the Kyoto Protocol emission reductions. Our results indicate that international trade is a significant factor in explaining the change in emissions in many countries, from both a production and consumption perspective. We suggest that countries monitor emission transfers via international trade, in addition to territorial emissions, to ensure progress toward stabilization of global greenhouse gas emissions.

The challenge to keep global warming below 2 °C

The latest carbon dioxide emissions continue to track the high end of emission scenarios, making it even less likely global warming will stay below 2 °C. A shift to a 2 °C pathway requires immediate significant and sustained global mitigation, with a probable reliance on net negative emissions in the longer term.

Reduced carbon emission estimates from fossil fuel combustion and cement production in China

Nearly three-quarters of the growth in global carbon emissions from the burning of fossil fuels and cement production between 2010 and 2012 occurred in China. Yet estimates of Chinese emissions remain subject to large uncertainty; inventories of China’s total fossil fuel carbon emissions in 2008 differ by 0.3 gigatonnes of carbon, or 15 per cent. The primary sources of this uncertainty are conflicting estimates of energy consumption and emission factors, the latter being uncertain because of very few actual measurements representative of the mix of Chinese fuels. Here we re-evaluate China’s carbon emissions using updated and harmonized energy consumption and clinker production data and two new and comprehensive sets of measured emission factors for Chinese coal. We find that total energy consumption in China was 10 per cent higher in 2000–2012 than the value reported by China’s national statistics, that emission factors for Chinese coal are on average 40 per cent lower than the default values recommended by the Intergovernmental Panel on Climate Change, and that emissions from China’s cement production are 45 per cent less than recent estimates. Altogether, our revised estimate of China’s CO2 emissions from fossil fuel combustion and cement production is 2.49 gigatonnes of carbon (2 standard deviations = ±7.3 per cent) in 2013, which is 14 per cent lower than the emissions reported by other prominent inventories. Over the full period 2000 to 2013, our revised estimates are 2.9 gigatonnes of carbon less than previous estimates of China’s cumulative carbon emissions. Our findings suggest that overestimation of China’s emissions in 2000–2013 may be larger than China’s estimated total forest sink in 1990–2007 (2.66 gigatonnes of carbon) or China’s land carbon sink in 2000–2009 (2.6 gigatonnes of carbon).

CO2 emissions from biomass combustion for bioenergy: atmospheric decay and contribution to global warming.

Carbon dioxide (CO2) emissions from biomass combustion are traditionally assumed climate neutral if the bioenergy system is carbon (C) flux neutral, i.e. the CO2 released from biofuel combustion approximately equals the amount of CO2 sequestered in biomass. This convention, widely adopted in life cycle assessment (LCA) studies of bioenergy systems, underestimates the climate impact of bioenergy. Besides CO2 emissions from permanent C losses, CO2 emissions from C flux neutral systems (that is from temporary C losses) also contribute to climate change: before being captured by biomass regrowth, CO2 molecules spend time in the atmosphere and contribute to global warming. In this paper, a method to estimate the climate impact of CO2 emissions from biomass combustion is proposed. Our method uses CO2 impulse response functions (IRF) from C cycle models in the elaboration of atmospheric decay functions for biomass‐derived CO2 emissions. Their contributions to global warming are then quantified with a unit‐based index, the GWPbio. Since this index is expressed as a function of the rotation period of the biomass, our results can be applied to CO2 emissions from combustion of all the different biomass species, from annual row crops to slower growing boreal forest.

INPUT–OUTPUT ANALYSIS AND CARBON FOOTPRINTING: AN OVERVIEW OF APPLICATIONS

This article provides an overview of how generalised multi-regional input–output models can be used for carbon footprint applications. We focus on the relevance and suitability of such evidence to inform decision making. Such an overview is currently missing. Drawing on UK results, we cover carbon footprint applications in seven areas: national emissions inventories and trade, emission drivers, economic sectors, supply chains, organisations, household consumption and lifestyles as well as sub-national emission inventories. The article highlights the multiple uses of generalised multi-regional input–output models for carbon footprinting and concludes by highlighting important avenues for future research.

The supply chain of CO2 emissions

CO2 emissions from the burning of fossil fuels are conventionally attributed to the country where the emissions are produced (i.e., where the fuels are burned). However, these production-based accounts represent a single point in the value chain of fossil fuels, which may have been extracted elsewhere and may be used to provide goods or services to consumers elsewhere. We present a consistent set of carbon inventories that spans the full supply chain of global CO2 emissions, finding that 10.2 billion tons CO2 or 37% of global emissions are from fossil fuels traded internationally and an additional 6.4 billion tons CO2 or 23% of global emissions are embodied in traded goods. Our results reveal vulnerabilities and benefits related to current patterns of energy use that are relevant to climate and energy policy. In particular, if a consistent and unavoidable price were imposed on CO2 emissions somewhere along the supply chain, then all of the parties along the supply chain would seek to impose that price to generate revenue from taxes collected or permits sold. The geographical concentration of carbon-based fuels and relatively small number of parties involved in extracting and refining those fuels suggest that regulation at the wellhead, mine mouth, or refinery might minimize transaction costs as well as opportunities for leakage.

A "carbonizing dragon": China's fast growing CO2 emissions revisited.

Chinas annual CO(2) emissions grew by around 4 billion tonnes between 1992 and 2007. More than 70% of this increase occurred between 2002 and 2007. While growing export demand contributed more than 50% to the CO(2) emission growth between 2002 and 2005, capital investments have been responsible for 61% of emission growth in China between 2005 and 2007. We use structural decomposition analysis to identify the drivers for Chinas emission growth between 1992 and 2007, with special focus on the period 2002 to 2007 when growth was most rapid. In contrast to previous analysis, we find that efficiency improvements have largely offset additional CO(2) emissions from increased final consumption between 2002 and 2007. The strong increases in emissions growth between 2002 and 2007 are instead explained by structural change in Chinas economy, which has newly emerged as the third major emission driver. This structural change is mainly the result of capital investments, in particular, the growing prominence of construction services and their carbon intensive supply chain. By closing the model for capital investment, we can now show that the majority of emissions embodied in capital investment are utilized for domestic household and government consumption (35-49% and 19-36%, respectively) with smaller amounts for the production of exports (21-31%). Urbanization and the associated changes in lifestyle are shown to be more important than other socio-demographic drivers like the decreasing household size or growing population. We argue that mitigation efforts will depend on the future development of these key drivers, particularly capital investments which dictate future mitigation costs.

CONSTRUCTING AN ENVIRONMENTALLY-EXTENDED MULTI-REGIONAL INPUT–OUTPUT TABLE USING THE GTAP DATABASE

The use of Multi-Regional Input–Output Analysis (MRIOA) for understanding global environmental problems is growing rapidly. Renewed interest in MRIOA has led to several large research projects focused on constructing detailed and accurate MRIOTs. However, very few researchers have made use of the already available and regularly updated database produced by the Global Trade Analysis Project (GTAP). We demonstrate and discuss how the GTAP database can be converted into an MRIOT without the need for additional balancing. An illustrative example uses the GTAP-MRIO to reallocate carbon dioxide emissions from producing to consuming countries. We suggest that an MRIOT that treats international transport exogenously is adequate until more reliable data on international transport margins and emissions are available. To focus resources and refine methods, a concerted research effort is needed to compare the results of the GTAP-MRIO model with the new MRIO datasets under development.

Structural analysis of international trade: Environmental impacts of Norway

Abstract Final demand purchases initiate production processes that ultimately lead to environmental impacts. With the increase in international trade, many production processes occur outside of the country of final consumption. Whilst several studies have evaluated the pollution embodied in consumption and trade flows, few studies have investigated the structural linkages between domestic consumption and production in foreign regions. In this article we apply three complementary approaches to study the production network leading from the Norwegian economy to domestic and international environmental impacts: (1) the consumption perspective identifies final demand purchases that produce environmental impacts; (2) the production perspective identifies the production processes generating the pollution for a given demand; and (3) structural path analysis is used to provide the linkages between the global production networks linking consumption and production. We find that the three approaches provide different, but complementary information. For policy to focus on both sustainable consumption and production, all three approaches are required to fully identify environmentally important sectors in an economy.

Consumption-based GHG emission accounting: a UK case study

Global GHG emissions continue to rise, with nearly a quarter of it due to trade that is not currently captured within global climate policy. In the context of current trade patterns and limited global cooperation on climate change, the feasibility of consumption-based emissions accounting to contribute to a more comprehensive (national) policy framework in the UK is investigated. Consumption-based emissions results for the UK from a range of models are presented, their technical robustness is assessed, and their potential application in national climate policy is examined using examples of policies designed to reduce carbon leakage and to address high levels of consumption. It is shown that there is a need to include consumption-based emissions as a complementary indicator to the current approach of measuring territorial emissions. Methods are shown to be robust enough to measure progress on climate change and develop and inform mitigation policy. Finally, some suggestions are made for future policy-oriented research in the area of consumption-based accounting that will facilitate its application to policy. Policy relevance Emissions embodied in trade are rapidly increasing and there is thus a growing gap between production emissions and the emissions associated with consumption. This is a growing concern due to the absence of a global cap and significant variation in country-level mitigation ambitions. Robust measurements of consumption-based emissions are possible and provide new insights into policy options. This includes trade-related policy (e.g. border carbon adjustments) and domestic policies (e.g. resource efficiency strategies). As climate policy targets deepen, there is a need for a broad range of policy options in addition to production and technological solutions. Consumption-based emissions are complementary to production-based emissions inventories, which are still the most accurate estimate for aggregated emissions at the global level. However, without consumption-based approaches, territorial emissions alone will not provide a complete picture of progress in regional and national emissions reduction.